std::sys

Functions

arg

fn arg(index: int) -> str?

Returns the command-line argument at index, or null if there isn’t one. When the script is run with the mimas command, index 0 is the script’s path as it was typed, and the arguments after -- start at index 1.

use std::sys;

// run as `mimas tool.mim -- input.txt`
let path = sys::arg(1) ?? "default.txt"; // "input.txt"

exit

fn exit(code: int) -> !

Ends the program immediately with the exit code code. Nothing after the call runs.

use std::sys;

if sys::arg(1) == null {
    print("usage: tool <file>");
    sys::exit(1);
}

exit ends the whole process. When mimas is embedded in a larger program, that program exits as well.

stdin

fn stdin() -> str!

Reads standard input until it ends and returns all of it as one string. Raises if the input can’t be read or isn’t valid UTF-8.

Input piped in from another program ends when that program finishes. In a terminal, it ends when you press Ctrl+D (Ctrl+Z then Enter on Windows).

use std::sys;

// run as `echo "a b c" | mimas count.mim`
let words = sys::stdin()!.trim().split(" ");
print(words.len()); // 3

file

fn file() -> str

Returns the absolute path of the source file that contains the call. For a script compiled from a string instead of a file, it’s the name the host gave that source.

Use it to find files stored next to the script (relative paths in std::fs start from the working directory instead).

use std::sys;

print(sys::file()); // /home/ada/projects/game/main.mim